This invention relates generally to the sewing machine arts and, in particular, to the portion of a sewing machine known as a presser foot.
Typical state of the art sewing machines utilize lower feeder devices and at least one upper presser foot to convey material to be sewn into the needle stitching area.
When two-ply or heavier materials are being sewn, the need often arises to lubricate the presser foot to keep the material from being bunched up. When such bunching does occur, the operator must slow the sewing rate or, in the worst case, the material is damaged, yielding an unusable product.
To accomplish the desired presser foot lubrication, it is known to use a silicone lubricating spray fluid from a conventional aerosol spray can. In using this spray method, however, the machine operator is required to repeatedly reach for the lubricating container and manually spray fluid onto the presser foot. Such manual lubrication method obviously results in a lower operator work rate.
Older prior art systems have attempted to achieve lubrication of a sewing machine presser foot as evidenced by U.S. Pat. Nos. 2,630,089 and 2,442,222.
In the Champlin U.S. Pat. No. 2,630,089, lubricating fluid is supplied by dripping it onto a sponge 16. The sponge 16 must then be squeezed by a clip 13 to accomplish the lubricating function. Even with the complex Champlin system, the front tip of the presser foot receives no lubrication.
The Uccellini U.S. Pat. No. 2,442,222 shows the use of a costly wick or brush system in which the presser foot must have specially machined ducts 20 formed therein and also a specially made reservoir 21 must be machined for each presser foot.
Such specialized systems as shown by Champlin and Uccellini are clearly not practical in today's market wherein literally hundreds of different presser feet are sold to accomplish specific desired results.
Accordingly, it is an object of the present invention to produce a presser foot lubrication system which does away with the need for the manual spray lubrication methods currently in use.
It is a further object of the invention to demonstrate a presser foot lubrication system which may be easily adapted to any presser foot without the need for the specialized and costly modifications shown in the prior art.
It is also an object to demonstrate a system wherein the entire presser foot, including the front tip, is efficiently lubricated.
It is a further object of the invention to demonstrate a presser foot lubrication system which has utility for all types of materials sewn, i.e. two-ply materials, plastics, rough materials, rubber compounds and materials having glue thereon from a prior screen printing process.
It is a still further object of the invention to produce a presser foot lubrication method having an efficient means of lubricant flow control by the operator in addition to a quick disconnect of the system when desired.
It is another object of the invention to provide a presser foot lubricating system which may be adapted for use with a liquid silicone lubricant or a compressed air lubricating means. These and other objects of the invention will become apparent to those of skill in the art in the specification which follows.